Stitching machine for a stack of sheets

ABSTRACT

A stitching machine for stitching a folded stack of sheets along a fold line by a stitching head cooperating with a clinching anvil, has two conveyors located on opposite sides of the clinching anvil for transporting and carrying the angularly spread stack portions, while the inside of the fold line slides on the clinching anvil whose position is adjusted to the thickness of the stack. Manual means are provided for raising and lowering the conveyors with the stacks also in accordance with the thickness of the transported stacks and with the adjusted position of the clinching anvil.

United States Patent 1191 1111 3,786,979 Miiller 1451 Jan. 22, 1974 [54] STITCHING MACHINE FOR A STACK OF 1,226,170 5/1917 Baumann 227/155 X SHEETS 1,911,159 511933 Metcalf 227/155 x 2,827,632 3/1958 Faeber 227/101 X Inventor: Hans Miiller, Zofingen, Switzerland Assigneez Grapha Maschinenfabrik Hans Muller AG, Zofingen, Switzerland Filed: Mar. 2, 1972 Appl. No.: 231,252

Foreign Application Priority Data Apr. 8, 1971 Switzerland 5210/71 US. Cl 227/44, 227/103, 227/155 Int. Cl B27f 7/08 Field of Search... 227/44, 45, 50, 99, 100, 101,

References Cited UNITED STATES PATENTS 4/1895 Jonas 227/102 Primary Examiner-Granville Y. Custer, Jr. Attorney, Agent, or FirmMichael S. Striker [57] ABSTRACT A stitching machine for stitching a folded stack of sheets along a fold line by a stitching head cooperating with a clinching anvil, has two conveyors located on opposite sides of the clinching anvil for transporting and carrying the angularly spread stack portions, while the inside of the fold line slides on the clinching anvil whose position is adjusted to the thickness of the stack. Manual means are provided for raising and lowering the conveyors with the stacks also in accordance with the thickness of the transported stacks and with the adjusted position of the clinching anvil.

10 Claims, 3 Drawing Figures PATENTEB JAN22I974 SHEET 2 0F 2 FIGQB FIG. 2

STITCHING MACHINE FOR A STACK OF SHEETS BACKGROUND OF THE INVENTION The present invention relates to a stitching machine by which folded brochures are stitched along a fold line between at least one stitching head and an associated clinching anvil whose height can be adjusted, and which is located between two transporting carriers or conveyors.

In known stitching machines of this type, the stitching heads are mounted in a manner which does not permit vertical adjustment. The apparatus is adjusted to the thickness of the folded stacks of sheets, such as brochures, by adjusting the height of the respective clinching anvils which are located between the two carriers or conveyors. In accordance with the prior art, the two conveyor chains run on guide bars which are fixedly secured to the frame of the machine, and cannot be adjusted in vertical direction.

When extremely thick stacks of sheets are to be stitched, the clinching anvil is located low between the two conveyors. Consequently, the clinching anvil cannot exactly center the folded stacks of sheets along the fold line, which results in improperly stitched and stapled brochures. If the paper is thin, the cover sheet may be torn during the stitching operation. Thin stacks are upwardly rejected at high speeds due to the fact that the clinching anvils are adjusted to a position which is too high as compared with the vertical position of the conveyors.

SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of the prior art in which the conveyors for the folded stacks of sheets are always spaced the same distance from the stitching heads, irrespective of the thickness of the stitched folded stacks.

With this object in view, the present invention provides a transporting carrier or conveyors which at least in the region of the clinching anvil, are adjustable in vertical direction to a higher and lower position, depending on the thickness of the transported and stitched stack. Manually operated means are provided for raising or lowering the transporting carrier for the folded stacks, such as brochures.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a front elevation, partially in section, illustrating a stitching machine in accordance with the invention;

FIG. 2 is a cross-sectional view taken on line Il-II in FIG. 1; and

FIG. 3 is a cross-sectional view taken on line IIIIII in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates a stitching machine for stitching folded stacks of sheets along the fold line, as substantially described in Swiss Pat. No. 337,177. A motor 2 is mounted in the machine housing 1, and drives over a belt 3, a wheel 4 which is fixedly secured to a shaft 5 .so that shaft 5 is rotated. Two chain wheels 6 are secured to drive shaft 5 which drive two endless conveyor chains 7. The upper runs of conveyors 7 are guided along bars 8 and 9, and the lower runs are guided by rigid bars 10 and 11. Bar 9 consists of several articulated bar portions 91, 92, 93 of which the centrally located bar portion 92 is visible in the sections of FIGS. 2 and 3. The bar 8 is constructed in the same manner so that the central bar portion 82 appears in FIGS. 2 and 3.

The supporting frame of the machine carries a fixed guide pin 33 engaging a slot 34 in bar portion 91 which has a guide pin 35 located in a slot 36 of bar portion 92. Bar portion 93 is pivotable about a fixed pivot pin 37, and has a fixed guide pin 38 engaging a slot 39 in bar portion 92. The several pin-and-slot connections permit raising and lowering of the central bar portion 92 and in a corresponding manner, of the central bar portion 82 of the bar means 8 to move these bar portions for instance between the positions respectively shown in full and dash-dot lines in FIG. 1.

The conveyors are formed by connected carrier links 12, best seen in FIG. 2, which carry a stack of folded sheets 13 forming a brochure or booklet, at a constant speed in the direction of the arrow F under the stitching heads 14 of a stitching apparatus 140, and over corresponding clinching anvils 22 which have upper edges slidingly engaging the central foldline of the respective stack 13 on the inner surface of the lowermost sheet.

Wheel 4 carries an eccentric pin 16 connected by a rod 17 with the stitching apparatus 140, and reciprocating the same along a stationary guide rail means 21 parallel to the conveyor chains 7. A double-armed lever 19 is pivotally mounted on a stationary pin 18 and is articulated at one end to a rod 20 articulately connected to the pin 16. The other end of the lever 19 is connected with the stitching heads 14 which are mounted in the stitching apparatus for vertical movement. Consequently, the stitching heads 14 carry out a reciprocating motion and additionally a cyclical up-and-down movement, as described in the Swiss Pat. No. 337,177. Each stitching head arrives at its lowest position when the entire stitching apparatus with the stitching heads 14 moves substantially at constant speed equal to the speed at which the stacks of sheets 13 are transported by the carrier links 12 of the conveyors 7. Each carrier link 12 engages one of the folded stacks of sheets 13, and the distance between the carriers 12 is selected so that the wheel 4 performs one revolution while one stack of folded sheets 13 is moved through the stitching apparatus. The carriers 12 are adjusted so that the portion of the spine or back of the folded stack of sheets, is located under the respective associated stitching head 14, when the respective stitching head 14 arrives in the lowest position thereof in which staples are driven through the spine of the folded stack of sheets, and clinched by the clinching anvil 22.

Each stitching head 14 cooperates with a clinching anvil 22 by which the staples are clinched after passing through the spine of the stack of folded sheets. Since the lowermost position of a stitching head 14, in which the stitching operation takes place, is invariable, it is necessary to provide adjustment means for the clinching anvils 22, in order to adapt the distance between the clinching anvils 22 and the lowest position of the stitching heads 14, to the thickness of the respective stacks of folded sheets.

For this vertical adjustment, toward and away from the respective stitching head 14, stitching apparatus 140 is provided with a vertical support plate 23 which carries the anvils 22, and has a lower end portion guided in a guide slot 24 of a support 25 for up-anddown movement. The support plate 23 supports a shaft 26 with an eccentric disc 27 which are arranged in a bore 28 in supporting means 25. The outer end of shaft 26 carries a fixed hand wheel 29, and when the hand wheel 29 is turned, the eccentric disc 27 engages with the lower portion of its periphery the wall surface of bore 28 and slides the support plate 23 with the clinching anvils 22 in accordance with the effective radius of the eccentric disc 27 in upward or downward direction toward and away from the stitching head 14.

In order to arrest the support plate 23 in a desired position corresponding to a series of stacks of folded sheets 13 which are to be stitched, shaft 26 passes through a plate 30 which slidingly engages supporting means 25, and has two vertical slots 31. In the supporting means 25, two clamping handles 32 are threaded, which pass through the slots 31 and can clamp the plate 30 firmly to the supporting means 25 so that the adjusted position of the clinching anvils 22 is secured.

in accordance with the invention, the uppermost carrier portions 12 of the conveyors 7 are to be placed at a level corresponding to the level of the adjusted clinching anvils 22 so that the folded stacks of sheets are properly transported by the carrier portions 12 while the respective clinching anvil 22 is located on the inside of the central fold line of the stack of sheets 13.

As explained above, the supporting bar means 8 and 9 are each composed of articulated bar portions 81, 91; 82,92; and 83, 93, so that the central bar portions 82 and 92 are together movable between higher and lower positions for raising and lowering the portion of the upper run of the conveyors 7 which passes through the stitching apparatus 140.

As best seen in FIG. 3, the bar portions 82, 92 are together supported on a vertical bar 40 which ismounted in bearings 42, 43, and also on another vertical bar 41, see FIGS. 1 and 3, which is mounted in a bearing 44 of the machine housing 1. A hand wheel 45 having a hub 45 provided with an inner'thread 46 is turnably but axially immovably mounted in a bearing 44 in the machine housing 1 coaxial with the bar 41 and the inner thread 46 engages the thread 47 of the vertical bar 41. By rotation of hand wheel 45, bar 41 is moved up and down. A shaft 48 is turnably mounted in the machine housing 1 and carries two fixed transversely projecting levers 49 and 50 which are articulated by ball joints 51 and 52 with the vertical bars 40 and 41, respectively, so that the bars 40 and 41 are connected for simulta neous vertical movement under the control of the hand wheel 45.

When the hand wheel 45 is rotated, vertical bar 41 is moved upward or downward, and shaft 48 is correspondingly turned so that bar 40 moves together with bar 41 the same distance in vertical direction.

Due to-thc fact that the central bar portions 82 and 92 are mounted on the vertical bars 40 and 41,. the central bar portions 82 and 92 move in a horizontal position up-and-down, while the bar end portions 91 and 93 are angularly displaced.

The up-and-down adjustment of the supporting bar means 8 and 9 raise and lower the parts of the conveyors 7 which move through the stitching apparatus so that the carriers 12 are raised and lowered to a level which corresponds to the level of the clinching anvils 22 previously adjusted in accordance with the thickness of the stack of folded sheets by operation of hand wheel 29.

It will be seen that members 29, 26, 27 and 23 constitute first adjusting means for adjusting the distance be tween the clinching anvil 22 and the stitching head 14 in accordance with the thickness of the folded stack of sheets, while members 45, 41, 40, 48, 49 and bar portions 82, 92, constitute second adjusting means for adjusting the height of the carriers 12 also in accordance with the thickness of the folded stack, and with the adjusted of the anvils 22.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of stitching machines for stitching stacks of sheets differing from the types described above.

While the invention has been illustrated and described as embodied in adjusting means for adjusting the height of conveyors transporting folded stacks of sheets in accordance with the thickness of the transported stacks, and with the previously adjusted position of the anvil of the stitching apparatus, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from spirit spriit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. Stitching machine for a stack of sheets, comprising transporting carrier means for transporting a stack of sheets along a path; stitching means including at least one stitching head and a clinching anvil respectively located above and below said path; first adjusting means for adjusting the position of said clinching anvil toward and away from said stitching head for varying the distance between said clinching anvil and said stitching head in accordance with the thickness of said stack; and second adjusting means for adjusting in accordance with the adjusted position of said clinching anvil and with the thickness of said stack, the position of at least the part of transporting carrier means which passes said stitching means.

2. Stitching machine as claimed in claim 1, wherein said transporting carrier means include two parallel endless conveyor means, each conveyor means having a plurality of carrier links supporting said stacks; and wherein said clinching anvil is located between said two endless conveyor means.

3. Stitching machine as claimed in claim 2, wherein said second adjusting means include support means for supporting said two conveyor means for movement along said path, and manual means connected with said support means for moving the same with-at least the parts of said two conveyor means passing said stitching means up and down in accordance with the thickness of said stack.

4. A stitching machine as claimed in claim 3, wherein said endless conveyor means have upper and lower runs each having carrier links, the carrier links of said upper run supporting said stacks; wherein said clinching anvil is located between said upper runs; and wherein said support means include two bar means supporting said upper runs of said conveyor means, respectively, said bar means having at least in the region of said stitching means two bar portions movable in vertical direction for raising and lowering said upper runs of said two conveyor means in accordance with the adjusted position of said clinching anvil and a linkage connected with said two bar portions and operated by said manual means.

5. Stitching machine as claimed in claim 4, wherein said linkage includes two vertical bars supporting said bar portions, two levers articulated to the lower ends of said vertical bars, and a shaft fixedly carrying said two levers; and wherein said manual means is operatively connected with one of said vertical bars for raising and lowering the same so that the other vertical bar is raised and lowered by said levers and shaft, and said two bar portions are raised and lowered by said vertical bars.

6. Stitching machine as claimed in claim 1, wherein said transporting carrier means include two transporting carriers located on opposite sides of said clinching anvil; wherein said first adjusting means include a vertical plate located between said two transporting carriers and supporting said clinching anvil, and manually operated means for raising and lowering said plate with said clinching anvil.

7. Stitching machine as claimed in claim 1, wherein said transporting carrier means include two transporting carriers located on opposite sides of said clinching anvil, and supporting said stack; and wherein said second adjusting means include linkage means for simultaneously raising and lowering both said transporting carriers with said stack to a level corresponding to the level of said clinching anvil, and manual means for actuating said linkage means.

8. Stitching machine as claimed in claim 1, wherein said stack of sheets is folded along a fold line forming two angularly spread stack portions resting on said transporting carrier means and being engaged by the same so as to be transported along said path; wherein said clinching anvil is located under the transported stacks 'slidingly engaging the inside of said fold line; wherein said stitching head is located above said clinching anvil and the folded stacks thereon; wherein said first adjusting means adjust said clinching anvil in vertical direction; and wherein said second adjusting means adjust at least said part of said transporting carrier means in vertical direction.

9. Stitching machine as claimed in claim 8, wherein said transporting carrier means include two parallel conveyors located on opposite sides of said clinching anvil for supporting said two angularly spread stack portions; and wherein said second adjusting means include two support means for guiding said conveyors in a horizontal plane, and manual means for raising and lowering said support means with said conveyors and folded stacks.

10. Stitching machine for a stack of sheets, comprising transporting carrier means for carrying and transporting a stack of sheets along a substantially horizontal path; stitching means for stitching the transported stack and located in said path; and adjusting means for vertically adjusting at least the part of said transporting carrier means which passes said stitching means, relative to said stitching means and in accordance with the thickness of the stack so that the relative position of said stitching means and of said path corresponds to the thickness of said stack. 

1. Stitching machine for a stack of sheets, comprising transporting carrier means for transporting a stack of sheets along a path; stitching means including at least one stitching head and a clinching anvil respectively located above and below said path; first adjusting means for adjusting the position of said clinching anvil toward and away from said stitching head for varying the distance between said clinching anvil and said stitching head in accordance with the thickness of said stack; and second adjusting means for adjusting in accordance with the adjusted position of said clinching anvil and with the thickness of said stack, the position of at least the part of transporting carrier means which passes said stitching means.
 2. Stitching machine as claimed in claim 1, wherein said transporting carrier means include two parallel endless conveyor means, each conveyor means having a plurality of carrier links supporting said stacks; and wherein said clinching anvil is located between said two endless conveyor means.
 3. Stitching machine as claimed in claim 2, wherein said second adjusting means include support means for supporting said two conveyor means for movement along said path, and manual means connected with said support means for moving the same with at least the parts of said two conveyor means passing said stitching means up and down in accordance with the thickness of said stack.
 4. A stitching machine as claimed in claim 3, wherein said endless conveyor means have upper and lower runs each having carrier links, the carrier links of said upper run supporting said stacks; wherein said clinching anvil is located between said upper runs; and wherein said support means include two bar means supporting said upper runs of said conveyor means, respectively, said bar means having at least in the region of said stitching means two bar portions movable in vertical direction for raising and lowering said upper runs of said two conveyor means in accordance with the adjusted position of said clinching anvil and a linkage connected with said two bar portions and operated by said manual means.
 5. Stitching machine as claimed in claim 4, wherein said linkage includes two vertical bars supporting said bar portions, two levers articulated to the lower ends of said vertical bars, and a shaft fixedly carrying said two levers; and wherein said manual means is operatively connected with one of said vertical bars for raising and lowering the same so that the other vertical bar is raised and lowered by said levers and shaft, and said two Bar portions are raised and lowered by said vertical bars.
 6. Stitching machine as claimed in claim 1, wherein said transporting carrier means include two transporting carriers located on opposite sides of said clinching anvil; wherein said first adjusting means include a vertical plate located between said two transporting carriers and supporting said clinching anvil, and manually operated means for raising and lowering said plate with said clinching anvil.
 7. Stitching machine as claimed in claim 1, wherein said transporting carrier means include two transporting carriers located on opposite sides of said clinching anvil, and supporting said stack; and wherein said second adjusting means include linkage means for simultaneously raising and lowering both said transporting carriers with said stack to a level corresponding to the level of said clinching anvil, and manual means for actuating said linkage means.
 8. Stitching machine as claimed in claim 1, wherein said stack of sheets is folded along a fold line forming two angularly spread stack portions resting on said transporting carrier means and being engaged by the same so as to be transported along said path; wherein said clinching anvil is located under the transported stacks slidingly engaging the inside of said fold line; wherein said stitching head is located above said clinching anvil and the folded stacks thereon; wherein said first adjusting means adjust said clinching anvil in vertical direction; and wherein said second adjusting means adjust at least said part of said transporting carrier means in vertical direction.
 9. Stitching machine as claimed in claim 8, wherein said transporting carrier means include two parallel conveyors located on opposite sides of said clinching anvil for supporting said two angularly spread stack portions; and wherein said second adjusting means include two support means for guiding said conveyors in a horizontal plane, and manual means for raising and lowering said support means with said conveyors and folded stacks.
 10. Stitching machine for a stack of sheets, comprising transporting carrier means for carrying and transporting a stack of sheets along a substantially horizontal path; stitching means for stitching the transported stack and located in said path; and adjusting means for vertically adjusting at least the part of said transporting carrier means which passes said stitching means, relative to said stitching means and in accordance with the thickness of the stack so that the relative position of said stitching means and of said path corresponds to the thickness of said stack. 